Meng Lingqian, Mezari Brahim, Goesten Maarten G, Hensen Emiel J M
Inorganic Materials Chemistry, Schuit Institute of Catalysis, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands.
Chem Mater. 2017 May 9;29(9):4091-4096. doi: 10.1021/acs.chemmater.7b00913. Epub 2017 Apr 18.
Hierarchical ZSM-5 zeolite is hydrothermally synthesized in a single step with cetyltrimethylammonium (CTA) hydroxide acting as mesoporogen and structure-directing agent. Essential to this synthesis is the replacement of NaOH with KOH. An in-depth solid-state NMR study reveals that, after early electrostatic interaction between condensed silica and the head group of CTA, ZSM-5 crystallizes around the structure-directing agent. The crucial aspect of using KOH instead of NaOH lies in the faster dissolution of silica, thereby providing sufficient nutrients for zeolite nucleation. The hierarchical ZSM-5 zeolite contains mesopores and shows excellent catalytic performance in the methanol-to-hydrocarbons reaction.
分级ZSM-5沸石通过一步水热合成法制备，以十六烷基三甲基氢氧化铵（CTA）作为介孔生成剂和结构导向剂。该合成的关键是用KOH替代NaOH。深入的固态核磁共振研究表明，在缩合二氧化硅与CTA的头基之间早期发生静电相互作用后，ZSM-5围绕结构导向剂结晶。使用KOH而非NaOH的关键在于二氧化硅的更快溶解，从而为沸石成核提供足够的养分。分级ZSM-5沸石含有介孔，并且在甲醇制烃反应中表现出优异的催化性能。
